1. Field of the Invention
The present invention relates to a castable polyurethane and, more particularly, to a polyurethane absent toxic and carcinogenic compounds.
2. Description of the Prior Art
One of the most widely used castable polyurethanes has been based on a prepolymer system including toluene diisocyanate (TDI), a polyalkylene glycol and MOCA which is 4,4-methylene-bis-(2-chloroaniline). This system gained much popularity in the past as a potting or casting material due to its ability to consistently cure to materials having exceptionally high physical properties. However, MOCA is now a proven carcinogenic substance and the high level of toxicity of the low boiling TDI requires that other castable urethane compositions be developed that are free of these obnoxious materials.